Normally in a pneumatic tire, recesses and protrusions are produced on the outer surface of a side wall portion due to the structure of tire constituting members. For example, at a splice portion or folded up end portions of a carcass layer, a sheet material from which the carcass layer is configured is laminated at the end portions or at the folded up portion of the carcass layer main body portion so the thickness is substantially that of two layers, and as a result recesses and protrusions are produced on the outer surface of the side wall portion.
On the other hand, decorative portions are provided on the side wall portion so that these recesses and protrusions are inconspicuous (camouflaged). For example, Japanese Patent No. 4640517 proposes partitioning the decorative portion in a grid by a plurality of circumferential direction rib bands extending in the tire circumferential direction and a plurality of radial direction rib bands extending in the tire radial direction to form ridges in partitioned multiple rectangular regions. This decorative portion can camouflage the recesses and protrusions as described above by a pattern contrast of the series of rectangular regions (rectangular patterns) and presence/absence of the ridges.
However, upon forming the circumferential direction rib band and the radial direction rib band as described above, the flow of air when forming the tire is hindered by these ribs so there is a possibility of occurrence of vulcanization failures. Also, cracking can easily occur at multiple intersecting sections formed by an intersection of the circumferential direction rib band and the radial direction rib band, which intersections have a problem that the durability of the decoration itself becomes poor.